While Nighttime Lights (NTL) have traditionally supported reactive disaster assessment, this study uses them for proactive analysis via a tip-and-cue method—commonly used in satellite surveillance, where NTL acts as the “tip” to guide very high-resolution (VHR) cueing. We demonstrate this through the case of post-Super Typhoon Yolanda (Haiyan) impact, recovery, and population mobility in Eastern Visayas, specifically in Tacloban City, Ormoc City, and the Municipality of Palo. Monthly composites of the NASA VNP46A2 VIIRS Lunar Gap-Filled BRDF NTL (May 2013 to May 2025) were used to minimize daily variability and produce stable NTL data. Temporal tip-and-cue used percent change relative to a 6-month pre-disaster average radiance baseline at the municipal or city level, identifying key impact moments during the disaster month and at the point of lowest radiance. Recovery was tracked using a 6-month rolling average to pinpoint return to baseline, onset of sustained recovery, and current status. We generated maps at 500m spatial resolution for the identified months, flagging areas of interest based on increases or decreases in NTL. These areas then cued the examination of VHR imagery (0.3–1m; Maxar and CNES/Airbus) and were further contextualized using news reports and situational updates from the National Disaster Risk Reduction and Management Council (NDRRMC). Findings indicate that NTL reflected not only power outages—especially in areas with damaged infrastructure—but also broader patterns of power utilization and human activity. Key points of impact show that declines aligned with zones affected by storm surges, flooding, and windborne debris, while increases marked areas of temporary aid, shelter, or energy infrastructure such as power and fuel sources. During recovery, declines pointed to displacement driven by protective policies and structures such as no-build zones, seawalls, and modified river channels, while increases indicated resettlement and expansion, with some supported by river walls and new roads. This spatiotemporal tip-and-cue approach highlights the value of NTL—when combined with contextual information—in efficiently assessing disaster impact, recovery progress, and population mobility for long-term planning.

This study is part of the 27^th Samahang Pisika ng Visayas at Mindanao (SPVM) National Physics Conference on 23-25 October 2025 at the University of San Agustin in Iloilo City.

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